U.S. patent number 7,486,245 [Application Number 11/522,966] was granted by the patent office on 2009-02-03 for mobile terminal with plural antennas.
This patent grant is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Young-eil Kim, Seong-soo Lee, Se-hyun Park, Byung-tae Yoon.
United States Patent |
7,486,245 |
Park , et al. |
February 3, 2009 |
Mobile terminal with plural antennas
Abstract
Disclosed is a mobile terminal with plural antennas. The mobile
terminal with plural antennas, comprising a circuit board formed
with a variety of elements, at least one first antenna formed on
one surface of the circuit board to transmit and receive a radio
signal for mobile communications, and at least one second antenna
formed on the other surface of the circuit board to transmit and
receive a radio signal for additional services. Accordingly, as the
size of the mobile terminal does not necessarily increase to have
plural antennas, the mobile terminal can be miniaturized.
Inventors: |
Park; Se-hyun (Suwon-si,
KR), Yoon; Byung-tae (Suwon-si, KR), Kim;
Young-eil (Suwon-si, KR), Lee; Seong-soo
(Suwon-si, KR) |
Assignee: |
Samsung Electronics Co., Ltd.
(Suwon-si, KR)
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Family
ID: |
37878446 |
Appl.
No.: |
11/522,966 |
Filed: |
September 19, 2006 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070139281 A1 |
Jun 21, 2007 |
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Foreign Application Priority Data
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Dec 16, 2005 [KR] |
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10-2005-0124851 |
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Current U.S.
Class: |
343/702;
343/700MS; 343/725; 343/846 |
Current CPC
Class: |
H01Q
1/243 (20130101); H01Q 9/0407 (20130101); H01Q
9/0421 (20130101); H01Q 21/28 (20130101) |
Current International
Class: |
H01Q
1/24 (20060101) |
Field of
Search: |
;343/702,700MS,725,846 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1324425 |
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Jul 2003 |
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EP |
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2001-0052175 |
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Jun 2001 |
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KR |
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Primary Examiner: Nguyen; Hoang V
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
What is claimed is:
1. A mobile terminal with plural antennas, comprising: a circuit
board formed with a variety of elements; at least one first antenna
disposed on one surface of the circuit board to transmit and
receive a first radio signal for mobile communications; and at
least one second antenna disposed on another surface of the circuit
board to transmit and receive a second radio signal for additional
services, wherein a ground of the at least one first antenna is
disposed on the one surface of the circuit board, and a first
radiation part of the at least one first antenna is disposed above
the ground of the at least one first antenna, wherein a second
radiation part of the at least one second antenna is disposed
directly on the other surface of the circuit board.
2. The mobile terminal of claim 1, wherein the at least one first
antenna and the at least one second antenna are planar
antennas.
3. The mobile terminal of claim 2, wherein the at least one first
antenna is at least one of a planar inverted F antenna (PIFA) and a
patch antenna.
4. The mobile terminal of claim 3, wherein the at least one second
antenna is at least one of the PIFA and the patch antenna.
5. The mobile terminal of claim 4, wherein the PIFA comprises a
PIFA radiation part for transmitting and receiving radio signals, a
feeding part for supplying an electric current to the PIFA
radiation part, a PIFA ground, and a short part for connecting the
PIFA radiation part and the PIFA ground.
6. The mobile terminal of claim 4, wherein the patch antenna
comprises a patch radiation part, which is plate-shaped, for
transmitting and receiving radio signals, a feed point for
supplying the electric current to the patch radiation part, and a
strip line for connecting the patch radiation part and the PIFA
ground.
7. The mobile terminal of claim 6, wherein a tip of the strip line
is vertically bent to penetrate the circuit board to connect the
second radiation part of the patch antenna to the ground of the
PIFA.
8. A mobile terminal with plural antennas, the mobile terminal
comprising: a circuit board formed with a variety of elements; at
least one first antenna disposed on one surface of the circuit
board to transmit and receive a first radio signal for mobile
communications; and at least one second antenna disposed on another
surface of the circuit board to transmit and receive a second radio
signal for additional services, wherein a radiation part of the at
least one second antenna is disposed directly on the other surface
of the circuit board, and wherein the at least one first antenna is
a planar inverted F antenna (PIFA) and the at least one second
antenna is a patch antenna.
9. The mobile terminal of claim 8, wherein the PIFA is disposed on
one side of the one surface of the circuit board, and the another
surface on which the patch antenna is disposed is a rear surface of
the circuit board corresponding to where the PIFA is formed.
10. A mobile terminal with plural antennas, comprising: a circuit
board formed with a variety of elements; at least one first antenna
disposed on one surface of the circuit board to transmit and
receive a first radio signal for mobile communications; and at
least one second antenna disposed on another surface of the circuit
board to transmit and receive a second radio signal for additional
services, wherein the at least one second antenna is connected to a
ground of the at least one first antenna via a path penetrating
through the circuit board, wherein the ground of the at least one
first antenna is disposed on the one surface of the circuit board.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims benefit under 35 U.S.C. .sctn.119(a) of
Korean Patent Application No. 2005-124851, filed Dec. 16, 2005 in
the Korean Intellectual Property Office, the entire contents of
which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a mobile terminal with plural
antennas. More particularly, the present invention relates to a
mobile terminal of a certain size with plural antennas.
2. Description of the Related Art
Recently, as the functions of a mobile terminal are diversified,
mobile terminals provide diverse services such as wireless Internet
connections, digital multimedia broadcasting (DMB) for viewing
programs of terrestrial and satellite origin, global positioning
system (GPS) receivers, camera, MP3 players, and, radio frequency
identification systems (RFID), as well as the communications
function.
To use the diverse additional functions other than communications,
multi-band mobile terminals are being developed, and to implement
the multi-band mobile terminals, an antenna capable of transmitting
and receiving a multi-band radio signal is needed. Such antennae
may require features such as compact size, broad bandwidth and high
gain.
In general, a mobile terminal is mounted with an external antenna
or an internal antenna. A mono-pole antenna and a helical antenna
are mainly used as external antennae, and a planar inverted F
antenna (PIFA) is mainly used as internal antennae.
The mono pole antenna and the helical antenna are externally
exposed so that the antenna can be damaged by an external impact.
When a user uses the mobile terminal, the antenna is often located
around the head of the user so that electromagnetic waves can
possibly have a bad effect on the user.
To solve weakness of the external antenna, the PIFA internal
antenna is often used.
Referring to FIG. 1, the PIFA 10 is implemented as a
three-dimensional structure including a ground 5, a radiation part
11, a feeding part 15 and a short part 13.
The radiation part 11 is formed on the upper part of the ground 5,
and the short part 13 is formed at the edge of the radiation part
11 to connect the ground 5 and the radiation part 11. The feeding
part 15 supplies an electric current to the radiation part 11.
Generally, impedance matching is determined according to the
location of the short part 13 and the length of the feeding part
15.
As such, the PIFA 10 is an internal antenna which can be embedded
in a mobile terminal, the weakpoints of the external antenna can be
essentially solved, and manufacturing the internal antenna is
easier than the external antenna. However, the PIFA 10 has the
limit to miniaturization due to a gap between the radiation part 11
and the ground 5.
Meanwhile, to support functions, such as DMB, GPS and RFID,
provided in different frequency bands, respectively, separate
antennas are required. However, if the mobile terminal is mounted
with plural PIFA antennas to support such functions, the size of
the mobile terminal gets larger or the number of the PIFAs mounted
in the mobile terminal is limited due to lack of space.
Recently, a planar antenna has been suggested for mobile
communications. The planar antenna can be formed on the printed
circuit board (PCB) so that extra space to place the antenna is
rarely needed. However, because of the nature of the planar
antenna, it is difficult to use with directional services so that
it can not be put to practical use for mobile communications.
SUMMARY OF THE INVENTION
An aspect of the present invention is to solve at least the above
problems and/or disadvantages and to provide at least the
advantages described below. Accordingly, an aspect of the present
invention is to provide a mobile terminal of a certain size with
plural antennas.
In order to achieve the above-described aspects of the present
invention, there is provided a mobile terminal with plural
antennas, comprising a circuit board formed with a variety of
elements, at least one first antenna formed on one surface of the
circuit board to transmit and receive a radio signal for mobile
communications, and at least one second antenna formed on the other
surface of the circuit board to transmit and receive a radio signal
for additional services.
The first antenna and second antenna may be planar antennas.
The first antenna may be at least one of a planar inverted F
antenna (PIFA) and a patch antenna.
The second antenna may be at least one of the PIFA and the patch
antenna.
The PIFA can comprise a radiation part for transmitting and
receiving the radio signal for mobile communications, a feeding
part for supplying an electric current to the radiation part, a
ground, and a short part for connecting the radiation part and
ground.
The patch antenna can comprise a radiation part, which is
plate-shaped, for transmitting and receiving the radio signal, a
feed point for supplying the electric current to the radiation
part, and a strip line for connecting the radiation part and
ground.
The first antenna may be the PIFA and the second antenna is the
patch antenna.
The PIFA can be formed on one side of one surface of the circuit
board, and the patch antenna is formed on the rear surface of the
circuit board corresponding to where the PIFA is formed.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The above aspect and other features of the present invention will
become more apparent by describing in detail exemplary embodiments
thereof with reference to the attached drawing figures,
wherein;
FIG. 1 is a perspective showing a circuit board of a mobile
terminal with plural antennas according to an embodiment of the
present invention;
FIG. 2 shows a cross sectional view of the circuit board of FIG. 1;
and
FIG. 3 shows a rear view of the circuit board of FIG. 1.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
Hereinafter, an embodiment of the present invention will be
described in detail with reference to the accompanying drawing
figures.
In the following description, the same drawing reference numerals
are used for the same elements throughout the drawings. The
detailed construction and elements are provided to assist in a
comprehensive understanding of the invention. Thus, it is apparent
that the present invention can be carried out without these
details. Also, well-known functions or constructions are not
described in detail since they would obscure the invention in
unnecessary detail.
A mobile terminal according to the present invention has plural
internal antennas and the plural internal antennas are formed on
both surfaces of a circuit board.
Each antenna is implemented as a planar antenna "Planar antenna" as
used herein refers to planar or thin three-dimensional antennas.
There are typically the 3D PIFA, PIFA, and patch antennas.
FIG. 1 is a perspective showing a circuit board of a mobile
terminal with plural antennas according to an embodiment of the
present invention, and FIG. 2 shows a cross sectional view of the
circuit board of FIG. 1.
As shown in FIGS. 1 and 2, a circuit board 1 has a first antenna of
the 3D PIFA type 10 on one surface and a second antenna of the
patch type 20 on the other surface.
The 3D PIFA 10 includes a ground 5, a radiation part 11, a feeding
part 15, and a short part 13.
The radiation part 11 converts an electric current into a radio
wave, and is plate-shaped. In FIG. 1, the radiation part 11 is
illustrated as a square plate but it can be also formed with a
diamond shape or a round shape and can be designed to have diverse
patterns using slits.
The feeding part 15 is perpendicularly connected with the radiation
part 11 to connect the radiation part 11 and the circuit board 1.
The feeding part 15 transmits the electric current supplied from
the circuit board 1 to the radiation part 11 so that the radiation
part 11 can transmit or receive the radio wave.
The short part 13 is formed parallel to the feeding part 15 to
connect the radiation part 11 and the ground 5. The short part 13
guides the electric current circulated in the radiation part 11 to
the ground 5.
Due to the feeding part 15 and the short part 13, the radiation
part 11 is distanced by a predetermined width from the circuit
board 1.
The ground 5 is formed on the circuit board 1 and can be designed
in diverse patterns according to the nature of the 3D PIFA 10 and
the patch antenna 20, and desired operation band. That is, the
pattern of the ground 5 can be implemented to optimize the the
S-parameters S11 of the 3D PIFA 10, S11 of the patch antenna 20,
and S12 between the 3D PIFA 10 and the patch antenna 20.
Hereinafter, the operation process of the 3D PIFA 10 will be
described. An electric current is supplied to the radiation part 11
through the feeding part 15, and the radiation part 11 converts the
electric current into a radio wave and radiates the radio wave. The
electric current returns to the ground 5 through the short part 13.
The radio wave externally received through the radiation part 11 is
supplied to the circuit board 1 through the ground 5.
The 3D PIFA 10 is omni-directional and is used to transmit and
receive a radio signal for mobile communications.
Meanwhile, the performance of the 3D PIFA 10 depends on the
bandwidth, return loss in the resonant frequency and impedance
matching efficiency. In general, impedance matching is determined
according to the location of the short part 13 and the length of
the feeding part 15.
FIG. 3 shows a rear view of the circuit board of FIG. 1. Referring
to FIG. 3, a patch antenna 20, a kind of a planar antenna, is
formed on the rear surface of the circuit board 1.
The patch antenna 20 includes a radiation part 25, a feed point 23,
a strip line 21, and the ground 5.
As shown in FIG. 2, the radiation part 25 is square-plate-shaped,
but also can be formed in a round shape. Additionally, the
radiation part 25 can be designed to have diverse patterns using
slits and the pattern can vary the operation band of the
antenna.
The strip line 21 is formed as a line extended from one side of the
radiation part 25 and can have plural bent parts according to the
operation nature of the antenna. The length of the strip line 21 is
designed in order for the radiation part 25 to resonate by matching
the real number part of the impedance to 50.OMEGA..
The tip of the strip line 21 is vertically bent to penetrate the
circuit board 1, and is connected with the ground 5 of the 3D PIFA
10. Therefore, the patch antenna 20 does not need a separate ground
5 so that the configuration of the patch antenna 20 can be
simplified.
The feed point 23 is formed at the other end of the strip line 21
extended from the radiation part 25 to supply an electric current
to the radiation part 25.
The patch antenna 20 is formed on the rear of the circuit board 1
corresponding to where the 3D PIFA 10 is formed. However, the patch
antenna 20 can also be formed anywhere on the rear of the circuit
board 1.
The 3D PIFA 10 transmits and receives radio signals for mobile
communications, whereas the patch antenna 20 can transmit and
receive the RFID radio signals, GPS satellite signals and DMB radio
signals. The patch antenna 20 is directional to the front surface
of the radiation part 25.
Recently, the mobile RFID (mRFID), combining the RFID system and
mobile telecommunications, are being provided. By mounting an
electronic tag, reader, antenna and processing module in a mobile
terminal, the mobile terminal can read information from another
electronic tag for user information service or can transmit
information to another device through the electronic tag. As an
RFID antenna used in mRFID transmits and receives a radio signal in
the 908.5.about.914 MHz band, the patch antenna 20 can be used for
the RFID antenna by matching the operation band of the patch
antenna 20 with the frequency band of the RFID radio signal.
Meanwhile, the GPS satellite system determines the location of a
mobile terminal by communicating radio signals with the mobile
terminal. So, for communication with the GPS satellite system, the
operation band of the antenna of the mobile terminal has to be
matched with the frequency band of the GPS satellite signal (L2
band: 1227.6 MHz, L1 band: 1575.42 MHz). Accordingly, the patch
antenna 20 can be used for the GPS antenna by matching the
operation band of the patch antenna 20 with the frequency band of
the GPS satellite system signal.
The DMB service is divided into the satellite based DMB service and
the DMB service. The satellite DMB service uses the S-band at
2.630.about.2.655 GHz which is higher than the terrestrial DMB
band. The terrestrial DMB service uses the frequency band at
204.about.210 MHz. Accordingly, the patch antenna 20 can be used
for the satellite DMB or terrestrial DMB by matching the operation
band of the patch antenna 20 with the corresponding frequency
band.
Meanwhile, in the above embodiment, the 3D PIFA 10 is used for
mobile communications, and the patch antenna 20 is used for the
RFID, GPS and/or DMB services. However, the 3D PIFA 10 can of
course be used for the RFID, GPS and/or DMB services, and the patch
antenna 20 for mobile communications.
Further, unlike the above embodiment, one or more patch antennas
can be formed on both surfaces of the circuit board 1.
As can be appreciated from the above description, the mobile
terminal of a certain size according to an embodiment of the
present invention can have plural antennas by forming the 3D PIFA
antenna and the patch antenna on opposite surfaces of the circuit
board. Accordingly, as the size of the mobile terminal does not
necessarily have to increase to have plural antennas, the mobile
terminal can be miniaturized.
While the invention has been shown and described with reference to
certain embodiments thereof, it will be understood by those skilled
in the art that various changes in form and details may be made
therein without departing from the spirit and scope of the
invention as defined by the appended claims.
* * * * *